As you know, I will never say anything is "easy." But there are some simple steps to help you get your first pull up. Focusing on the negative (the lowering part of the movement) at the start really goes a long ways towards getting your first pull up. Then you'll also want to do passive hangs. (Me: hanging from a bar at the gym. Passerby: "That's exercising?" Me: "Yep.') But the two best preparatory exercises for doing pull ups are:
1. Lat pull downs.
2. Machine assisted pull ups.
The assisted pull up machine is one of the best gadgets at the gym. Especially the one where you have to stand. The goal is to build up the strength in your arms and back to the point where you can lift your own weight. I am 235 pounds so that wasn't an easy task. But stick with it and you'll get there, even if it takes you a year and a half like it did me.
Have a wonderful day!